The Mason-bees 



wards the hollow of a cell. How Is it apprised 

 whether the part below is empty or full? Its 

 organs of information are undoubtedly the 

 antennae, which feel the ground. They are 

 two fingers of unparalleled delicacy, which 

 pry into the basement by tapping on the part 

 above it. Then what do those puzzling or- 

 gans perceive? A smell? Not at all; I al- 

 ways had my doubts of that and now I am 

 certain of the contrary, after what I shall de- 

 scribe in a moment. Do they perceive a 

 sound? Are we to treat them as a superior 

 kind of microphone, capable of collecting the 

 infinitesimal echoes of what is full and the 

 reverberations of what is empty? It is an at- 

 tractive idea, but unfortunately the antennae 

 play their part equally well on a host of oc- 

 casions when there are no vaults to reverbe- 

 rate. We know nothing and are perhaps de- 

 stined never to know anything of the real 

 value of the antennal sense, to which we have 

 nothing analogous; but, though it is impos- 

 sible for us to say what it does perceive, we 

 are at least able to recognize to some extent 

 what it does not perceive and, in particular, 

 to deny it the faculty of smell. 



As a matter of fact, I notice, with extreme 

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